condition mean min max ZT0-3 7.52535 7.1814 7.869300000000001 ZT4-7 7.755475000000001 7.755475000000001 7.755475000000001 ZT8-11 11.0972 11.0972 11.0972 ZT12-15 0 0 0 ZT16-19 9.591515000000001 9.591515000000001 9.591515000000001 ZT20-23 8.3311 8.3311 8.3311